Cam grinding apparatus



Dec. 7, 1937. c, J GREEN 2,101,796

CAM GRINDING APPARATUS Filed Nov. 27, 1936 3 Sheets-Sheet l awe/M900 UL HRENL'EJ GREEN Dec. 7, 1937. c. J. GREEN CAM GRINDING APPARATUS Filed NOV. 27, 1936 5 Sheets-Sheet 2 ELFIPENDE J GREEN Dec. 7, 193 7.

c. J. GREEN 2,101,796

CAM GRINDING APPARATUS 5 Sheets-Sheet 3 Filed NOV. 2'7, 1936 Ema/14M EL FIRENCE J GREEN Patented Dec. 7, 1937 2,101,796 4 UNITED STATES PATENT orrics CAM GRINDING APPARATUS 'Ciarence J. Green, Worcester, Mass. assignor to Norton Company, Worcester, Masa, a corporation of Massachusetts Application November 27, 1936, Serial No. 11am 10 Claims. (01. 51-101 The invention relates to grinding machines, depending nut is which meshes with a rotatable and more particularly to a camshaft grinding feed screw lil which'is rotatably supported in machine. bearings (not shown) in the base "I. The feed One object of the invention is to provide a screw 20 is provided with an integral shaft 2| simple and thoroughly practical machine for which extends from the front of the machine 5 grinding a plurality of cam blanks on an inbase. A manually operable hand wheel 22 is tegral camshaft. A further object of the invenmounted on the end of the feed screw shaft 2| tion is to provide an improved mechanism for and is arranged so that it may be rotated to producing a relative feeding movement between cause a transverse adjustment of the wheel I4 the cam blank and the grinding wheel to faciiieither toward or from the work supporting 10 tate grinding the cam blanks to a predetermined table II. size. Another object of the invention is to pro- The work supporting table II is moved longivide an automatic cam grinding machine with tudinally relative to the base ill by means of a an improved feed control mechanism in which hydraulically operated mechanism comprising a the master cam and master cam roller are actucylinder 25 which is fixed to the base ii). A pis- 15 ated to control both the contour and sizing of the ton 26 is slidably mounted within the cylinder cam blanks. Other objects will be in part ob- 25 and is connected by means of a piston rod 21 vious or in part pointed out hereinafter. with a bracket 23 depending from the table I I.

The invention accordingly consists in the fea- Fluid under pressure may be admitted either tures of construction, combinations of elements, through a pipe 29 into a cylinder chamber 30 20 and arrangements of parts, as will be exempli- (Fig. 2) or it may be admitted through a pipe fied in the structure to be hereinafter described, 3| into a cylinder chamber 32 to cause the piston and the scope of the application of which will and work supporting table II to move toward be indicated in the following claims. the left (Fig. 2). The admission of fluid under In the accompanying drawings in which is pressure to the cylinder chambers and 32 is 25 shown one of the possible embodiments of the controlled by a valve mechanism to be hereinmechanical features of this invention, after described.

Fig. 1 is a fragmentary end elevation of a The longitudinally movable work table H supgrinding machine, having parts broken away ports a pivotally mounted rock bar 35 which is 30 and shown in section to show the improved feedsupported in bearings 35 and 31 which are flxed- 30 ing mechanism; ly mounted on the upper surface of the table Ii Fig. 2 is a diagrammatic view, showing the (Figs. 1 and 5), and is arranged so that it may piping diagram and the electrical control circuit; be rocked about an axis which is substantially Fig. 3 is a fragmentary front elevation, on an parallel to the axis of rotation of the grinding 5 enlarged scale, showing the improved feeding wheel l4. The rock bar 35 is provided with a ro- 35 mechanism; tatable shaft or headstock spindle which, as illus- Fig. 4 is a fragmentary sectional view, taken trated in the drawings, may be designated a approximately on the line 44 of Fig. 3; and master camshaft 38 having a camshaft support- Fig. 5 is a fragmentary perspective view, showing center 39. The master camshaft 38 is sup- 40 ing the arrangement of the master cams, master ported in bearings 40 and 4|. The rock bar 35 40 cam follower, camshaft and grinding wheel supalso supports a footstock 42 which in turn is port. I provided with a footstock center 43. The head- A cam grinding machine has been illustrated stock center 39 and the footstock center 43 are in the drawings having a base I 0 which supports ,arranged rotatably to support a camshaft 44 45 a longitudinally movable work table II on a flat having a plurality of cams 45 to be ground. 45

way l2 and a V-way I3. The base III also sup- In order that the cams- 45 on the camshaft ports a rotatable grinding wheel I4 which is 44 may be ground to a predetermined size and mounted on a rotatable wheel spindle I 5 iourcontour, it is desirable to provide a plurality of naled in bearings (not shown) in a transversely master earns 48 for controlling the rocking move- Jii) movable wheel slide l6. ment of the rock bar 35 so as to rock the cam- The wheel slide l6 may be adjusted transshaft 44 being ground toward and from the versely relative to the base III by a feeding mechperiphery of the grinding wheel l4 so as to genanism which may be actuated eithermanually or erate a predetermined shape on the cam blanks automatically, as desired. In the preferred con- 45. A plurality of master cams 43 are mounted struction. the heel slide Hi is provided with a 0n the headstock spindle or master camshaft 38 predetermined contour but also to a predeterin axial alignment with the axis of the camshaft 44 being ground. A mastercam roller or follower I is slidably mounted on a rotatable shaft it which is rotatably supported in a pair of spaced brackets 5| (Fig. 1). The master cam roller 40 is preferably indexed automatically as the table II is moved longitudinally to. position the master cam roller 49 opposite the. master cam ll which corresponds to the cam 45 being ground on the camshaft 44. The details of the master cam roller indexing mechanism have not been illustrated since this feature is not considered part 'of the present. invention. For a detailed disclosure of the automatic shifting of the master'cam roller, reference may be had to the prior United States Patent No. 1,783,755 to Trefethen and Belden datedDecember 2, 1.930 and also to the United States Patent No. 2,022,178 to Belden and Bilven dated November 26, 1935.

In order to grind the cam blank not only to a mined size, it is desirable to provide a feeding mechanism for causing a relative approaching and receding movement between the cam 45 being ground'and the grinding wheel H. In the preferred form of this invention, I provide a feeding mechanism which causes the master cam roller ll to approach or recede from the axis of the grinding wheel so as to change the position of the stroke of oscillation of the rock bar .35 and 'to produce either a relative approaching or receding movement between the cam 45 being ground and the grinding wheel ll. In the con'-.

struction as illustrated in the drawings, the spaced brackets 5| which form a rotatable support for the shaft II and master cam roller or follower 40 are formed as an integral part of a transversely movable slide 55 which is provided with a dovetailed slideway l mating with a dovetailed projection 51 which is formed integral with the table H.

In the preferred form, a hydraulically actuated feeding mechanism is provided comprising a fluid pressure cylinder Ill which supports a slidably mounted piston 6| on a piston rod 62. The piston rod 02 extends through both ends of the cylinder 00 and is providedwith a rack bar 63 at its lower end which meshes with a gear 04 rotatably sup-' ported on a shaft 65 which is Journaled in a bracket 86 which is fixed to the upper surface of the dovetailed way 51. The cylinder '0 is sup ported by an upwardly extending bracket 61 which is formed integral with the bracket 68. A cam or eccentric BI is mounted on the outer end of the shaft 65 and is arranged to engage a follower 6! which is fixedly mounted to a web I0 formed integral with the slide I5. It will be readily apparent from the foregoing disclosure that when the cam or eccentric 68 is rotated by the rack 63 and gear M, a transverse movement will be transmitted to the slide-l5 to feed the master cam roller 49 so as to cause the camshaft H and cam 48 being ground to approach or recede from the grinding wheel l4, so that it may be ground to a predetermined size.

It is desirable that a suitable mechanism be provided to hold the follower i! in engagement with the periphery of the cam or eccentric I. A spring pressure device is'preferably utilized comprising a spring II which is enclosed within a cylinder II. The cylinder 12 contains a slidably mounted piston 13 which is connected by a piston rod 14 with a bracket II which is flxedly mounted on the upper surface of the dovetailed way 51. The compression spring ll surrounds the piston flxed .in the lower end of the cylinder 9|.

rod 11 and is interposed between the piston 13 and a cylinder head 16 which encloses the lower end of the cylinder 12. The compression spring II is arranged to move the slide 65 in a direction toward the right (Figs. 1 and 4) so as to maintain the follower 6! in operative engagement with the eccentric or cam 68.

When it is desired to cause an infeeding movement of the camshaft N towardv the grinding wheel 14, fluid under pressure is admitted through pipe into a cylinder chamberfll to cause a downward movement of the piston 6| which serves to move the rack bar ll downwardly and rotates the gear 64 in a counterclockwise direction (Fig. 1), thereby rotating the shaft" and cam or eccentric II in a clockwise direction (Fig. l) to transmit a transverse movement to the slide 55 through the follower I! and thereby shifts the axis of the master cam roller shaft 50 toward the axis of the grinding wheel spindle ll so as to feed the cam blank 45 being ground into the operative face of the grinding wheel H to grind the cam blank to a predetermined size.

A spring .2 surrounding the piston rod 82 and interposed between the piston Cl and the lower cylinder head serves to cause an upward movement of the piston 8i when the fluid under pressure in'the pipe 80 is cut off. This upward movement of the piston Oi rotates the cam or eccentric 8| in a clockwise direction to cause a transverse movement of the slide it toward the right (Fig. 1) to cause the master cam roller shaft ii to recede from the axis of the wheel spindle ll so as to cause a separation of the cam 45 and the grinding wheel M. I

It is desirable to provide a suitable means for stopping the infeeding movement when the cam has approached the grinding wheel and has been ground to a predetermined size. An adjustable collar II is provided on the piston rod 62 and is arranged to be locked in adjusted position thereon by means of aset screw .6. The stop collar 85 is arranged so as to engage the upper surface of a cylinder head I] and thereby to limit the downward movement of the rack 83 and the rotary movement of.the feed cam or eccentric 88. The rate of infeeding movement of the cam may be regulated by a valve 88 in the pipe Ill. Fluid under pressure is admitted through the valve 88 and pipe 80 by a mechanism to be hereinafter described.

In order that the master cams ll may be maintained in operative engagement with the master cam roller 4! during the grinding operation on a cam blank 45, a yieldable pressure device is provided which serves yieldingly to maintain the master cam 40 in contact with the follower roller I). As shown in the drawings, the rock bar I is provided with an arm II. A cylinder 9| is pivotally supported on a bracket by means of a circular clamping band (not shown). The cylinder 9| contains a piston 82 which is connected by a piston rod 03 with a stud M on the arm 90. A spring I! surrounds the piston rod 93 and is contained within the cylinder 9| between the piston 02 and a cylinder head 08 which is The spring II is compressed to a sufficient extent to maintain the master cam II in operative contact with the master cam roller 49 during the grinding operation.

A fluid pressure mechanism is provided to rockuctcamllandgrindingwheelll er ll.

Afluid pressuresystemisprovidedtoactuate the various mechanisms of the machine in' a definite timed relationship with each other. A rescrvoir II! is provided in the base of the ma-.

chine. Fluid is pumped from reservoir II! through apipe Iltbymeansofafluidpressure pump lll which forces fluid thro h spine l and I to a main control valve III. l 'luid under pressure passing through the pipe III also passes through a cycle pilot valve III which is operatively connected to shift the main control valve III in either direction. A pressure relief valve III is operatively connected with the pump Ill so that if the pressure within the system exceeds a predetermined-pressure, excess fluid pressure will open the relief valve III and return the excess fluid through a pipe III into the reservoir I".

The main control valve III is connected by pipes with the various operating mechanisms of the machine. A pipe III is connected between the main control valve II. and the feed cylinder I. The main control valve III is connected by the pipe $8 with the rock bar cylinder SI and serves to rock the rock bar It to an inoperative positionafteracamhasbeengroundtothe predetermined slae and contour and before the table is indexed longitudinally. The cycle pilot valve III is connected by pipes II and III with valve chambers II. and II! in oppositeends of the main control valve III. The valve III is arranged so that when shifted in either direction, it will cause the main control valve II. to shift and thereby control the cycle of operation of the machine.

The main control valve II. is connected by the pipe I20 with a table reversing valve III which in turn is piped and connected with a pilot valve III. The reverse valve III and pilot valve I22 are connected to control the admission of fluid under pressure to the cylinder chambers 3. and 32 of the flu d pressure cylinder 25.

A pipe I25 is connected between the main control valve III and a slow speed valve I2. The valve I26 is interconnected with the pilot valve- I22 and is arranged to slow down the movement of the table II to a predetermined slow speed for truing the grinding wheel.

A cycle control mechanism is provided for controlling the cycle of operation of the machine. A cycle counting and control mechanism III is mounted above the master cam roller casing 55 and is connected to and actuated by the rocking movement of the rock bar 35. After a pre-' determined number of rotations of the camshaft N in operative relation with the grinding wheel ll, an electric switch I2! is actuated which in turn serves through an electrical circuit to enerelse a solenoid m and thereby to shift the cycle pilotvalve III whichinturnshiftsthemain control valve and changes the direction of movement of fluid under pressure within the system.

aromas separstcdbeforethetraversingofthe' started. lhisme'chanismmaycom-- apart of the present invention, but have -merely been illustrated to show an operative. cycle oroontrollingthegrlndingoia-camshaft. This pipingandelectrica'l control issubstantially iden- Assuming the table u: m be in its extreme lefthand or loading position, the machine is started in operation by first pushing anelcctric control 7 button (not shown) to start the rotation of the grinding wheel II, then pushing a' second button (not shown) to start the rotation of the fluid pressure pump Ill. Push button Ill is closed to start the rotation of the work driving motor III.

The workpiece. such as a camshaft 44, is then loaded in the machine and supported between the headstock center I! and footstock center 43. A work drive clutch (not shown) is'then engaged to start rotation of the master camshaft and the camshaft to be ground. The cycle control push button I is then closed to render the mercury switch III operative so that the machine is then under the control of the cycle counting mechanism I28. A hand lever I is then moved toward the right which serves through connections (not shown) to move the dog lever Ill out of the path of the table stop dog ISI. This movement allows the released tension of the spring pressed roller I52 to rock the levers IN and I in a clockwise direction (Fig. 2) which serves to shift the valve III toward the left, as viewed in Pig. 2, so that fluid under pressure passing through the pipe III into the valve I2I passes outwardly through the pipe 2! into the cylinder chamber 3| to move the piston 23 and table II toward the right to bring the first cam on the camshaft ll into operative grinding relation with the wheel I4.

The longitudinal movement of the table continues until the next dog ISI engages the dog lever In which serves to rock the lever I53 from the position shown in Fig. 2, thereby moving the valve stem III toward the right to cut oil fluid from the pipe 29 and thereby stop the movement of the table II. When the lever liireturns to the position illustrated in Fig. 2, a limit switch I55 is closed, serving to energize a relay I56 which in turn energizes the solenoid I51 to withdraw the pawls I50 from engagement with a ratchet wheel I5! so as to allow the released tension of a spring to return the ratchet wheel I5! and the mercury switch I2! to a starting position ready for the control of the next grinding cycle. When lever I45 is shifted toward the left at the start of the grinding cycle,'the limit switch Ill is closed and the solenoid III is energized to shift the cycle pilot valve III upwardly so as to admit fluid under presure from the pipe Ill, through the valve III and through a pipe II into the chamher I II to move the main control valve III toward the right, as viewed in Fig. 2. This movement of the main control valve II! serves to cut oil the flow of fluid through the pipe I2. to the table reversing valve Ill and serves to admit the flow of fluid under pressure through the pipe III and a pipe I! into acyiinder chamber I to move a piston I" toward the left (Pig. 2) which serves thereby serves to move the dog lever I55 out of .the path of the table dog I".

At the same time, fluid under pressure passing through the pipe III passes through an adjustable throttle valve 55, through a pipe 55, into a cylinder chamber II to cause a feeding movement of the master cam follower roller 45. At the same time the main control valve Is shifted, as above mentioned, fluid is allowed to exhaust from the cylinder chamber 51 to allow'the rock bar 55 to rock so that the master cam 45 engages the master cam roller 45. Rotation of the master cam roller 45 in contact with the master cam 45 serves to rock the camshaft 44 to grind a cam blank 45 to a predetermined contour. Each time the rock bar'55 rocks toward and from the grinding wheel, the cycle control counting device I25 is operated, and after a predetermined number of oscillations of the rock bar 55 serves to rock the mercury switch I25 and thereby break the circuit, which serves to deenergize a relay I III tobreak the circuitand deenergize the solenoid I" which in turn releases the tension of the spring "I to permit the cycle pilot valve III to move into the full line position, as illustrated in Fig. 2. This movement of the cycle pilot valve III allows fluid passing through the pipe I 55 to enter the valve III, to pass out through the pipe I" into a valve chamber H5 at the right-hand end of the main control valve III to move the valve toward the left, into the position of the parts illustrated in Fig. 2. This movement of the main control valve II5 again opens the passage of fluid through the pipe I25 to valve I 2I and allows it to pass out through the pipe 25 to the cylinder chamber 55 to again index the piston 25 and the table II longitudinally to present the next cam 45 into operative relation with the grinding wheel I4.

This cycle of operation is continued until each one of the successive cams 45 on the product camshaft 44 is ground to the desired size and contour. Each time the table II is indexed longitudinally to present a new product cam 45 to the grinding wheel I4, the master cam roller 45 is indexed longitudinally by an indexing mechanism, not shown in the present application. This feature is not considered to be part of the present invention and consequently has not been illustrated in detail. For reference to the details of the master cam roller indexing mechanism, reference may be had to the above-mentioned patent to Belden and Silven No. 2,022,178 dated November 26, 1935. When the dog lever I55 is moved out of the path of the dog I5I, the released tension of the spring-pressed roller I52 serves to rock the levers I55 and I54 in a clockwise direction.

This movement serves to open the limit switch I55 which in turn serves to deenergize the solenoid I51 and allows the pawl I 55 to engage the ratchet wheel I55 so that upon oscillation of the rock bar 55 the pawl I55 may be oscillated to turn the ratchet wheel I55 after each oscillation of the rock bar 55 to control the cycle of grinding on the cam 45. After thecam 45 has rotated through a predetermined number of rotations in contact with the grinding wheel I4 during the grinding operation, the mercury switch I25 is rocked to break the-circuit and the breaking of the circuit serves to release the relay I'll to deenergize the solenoid I55, and the released tension of the spring I'II then returns the valve III into the position illustrated in Fig. 2. In' this position of the valve III fluid under pressure from pipe I55 2,101,700 to rock a lever m in a clockwise direction and passes through valve'III and pipe I" into the chamber H5 at the right-hand end (Fig. 2) of the main control valve IIII. This movement of the main control valve II5 serves to allow fluid under pressure to pass through the pipe I25 into the valve I2I which has previously been moved toward the left when the dog lever I55 was withdrawn from the table dog I5I so that fluid under pressure entering the valve I2I passes out through pipe 25 to index the piston 25 and table II toward the right. This movement continues until the next dog I5'I engages the dog lever I55 to again stop the table movement when the next cam is in operative relation with the grinding wheel.

This cycle of events continues until the last cam 45 on the left-hand end of the camshaft 44 to be ground (Fig. 5) has been ground, after which the table II is traversed to a further position toward the right so that the wheel I4 is to the left of the last cam 45 on the shaft 44. During this movement beyond the last cam 45 on the shaft 44, a dog "4 engages a plunger I which serves to rock a lever I15 and allows a pin I" to move freely over a surface I15 and the levers I55 and I15 to take the position shown in Fig. 2. The pin I'I'I holds the limit switch I55 open. This opening of limit switch I55 serves to deenergize the solenoid I51 and allows the pawl I55 to drop into operative contact with the ratchet wheel I55. At the same time, a table reversing dog. I55 engages a table pilot valve lever III and rocks it in a clockwise direction (Fig. 2), serving to move the valve I22 toward the left, as viewed in Fig. 2. This movement serves to allow fluid under pressure passing through a pipe I52 into the table pilot valve I22 to pass outwardly therefrom through a pipe I55 into a valve chamber I 54 in the lefthand end of the table reverse valve I2I. Fluid under pressure entering the reverse valve chamber I54 shifts the valve toward the right, as viewed in Fig. 2, so that the arrow point passes over the high point of the spring-pressed roller I52 and the arrow point serves to hold the reverse valve I2I in a reverse position so that fluid under pressure passing through the pipe I into the valve I2I then passes out through the pipe 5I into the cylinder chamber 52 of the table operating cylinder 25 to cause the table II to move rapidly through an idle stroke toward the left (Fig. 2).

This movement serves to return the table II to its initial or starting position. When the table II approaches the left-hand end of its movement, a truing dog on the table II engages the roller I55 and depresses the same, which serves to shift the truing speed valve I25 toward the right (Fig. 2) so that fluid under pressure exhausting from the table cylinder 25 passes through a V-port I 51 to throttle the exhaust thereof and to regulate the speed of movement of the table II while a truing tool (not shown) mounted on the table II passes across the face of the wheel I4, whereupon a depending projection of the truing dog engages the lever I5I to rock it in a counterclockwise direction to move the valve I22 toward the right (Fig. 2), serving to admit fluid under pressure entering through pipe I52 into the valve I22, out through a pipe I55, into a valve chamber I55 at the right-hand end of the table reversing valve I2I. This movement serves to shift the table reversing valve I2I into the position illustrated in Fig. 2, so that the valve, is in position ready to start the next grinding cycle after the finish ground camshaft N has been removedand replaced with a new camshaft to be ground. When the reverse valve III shifts into the position above described, the table Ii starts its return stroke toward the right to pass the diamond across the face of the wheel a second timeand continues this motion until the dog lever ill engages the table stop dog III which stops the table It Just before the first cam 4 moves into operative relation with the grinding wheel I. The machine is then in a stopped position and the ground camshaft may be readily removed and replaced with a fresh camshaft to be ground.

Dining the wheel truing operation the headstock motor I is stopped by means of the adiustably mounted table dog it! to permit the removal of the finish ground camshaft 44 from the machine during the truing operation. Dog I" slides over and depresses arod iii of a limit switch I92 whichbreaks the circuit to deenergize a relay I98 which stops the headstock motor I4 I. As the table i I reciprocates during the truing operation, the table dog I90 slides over the rod i9i and upon completion of the truing operation, the table ii moves to the table stop dog l5i at the end of the grinding cycle, dog I90 still maintaining contact with the rod i9 i. Upon starting of the grinding cycle, the dog I90 will come out of contact with the rod Ni and close the limit switch I 92 to start the headstock motor I before the first cam 45 comes into operative relationship with the grinding wheel ll.

It will thus be seen that there has been provided by this invention apparatus in which the various objects hereinabove set forth together with many thoroughly practical advantages are successfully achieved. As many possible embodiments may be made of the above invention and as many changes might be made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

I claim:

1. In a camshaft grinding machine, a rotatable grinding wheel, a longitudinally movable rock bar, a rotatable master camshaft on said bar having a plurality of master cams thereon, a rotatable work support on said bar which is arranged to support a camshaft in axial alignment with said master camshaft, means synchronously to rotate said camshaft and master camshaft, a rotable master cam follower roller associated with said master cams which is arranged to cause a transverse movement between the grinding wheel.

and camshaft to grind a predeterminedcontour on a cam blank, and means to move said master cam roller transversely during the grinding operation to produce a relative approaching movement between the camshaft support and grinding wheel to grind the cam blank to a predetermined size.

2. In a camshaft grinding machine, a rotatable grinding wheel, a longitudinally movable rock bar, a rotatable master camshaft on said bar having a plurality of master cams thereon, a rotatable work support on said bar which is arranged to support a camshaft in axial alignment with said master camshaft, means synchronously to rotate said camshaft and master camshaft, a rotatable master cam follower roller associated with said master cams which is arranged to cause a transverse movement between the grinding wheel and camshaft to grind a predetermined contour on a cam blank, means including a rotatable cam to move said master cam roller transversely during the grinding operation, and means to actuate said cam to move said roller and thereby produce a relative approaching movement between the camshaft support and grinding wheel to grind a cam blank to a predetermined size; a

3. In a camshaft grinding machine. a rotatable rinding wheel, a longitudinally movable rock bar, a rotatable master camshaft on said bar having a plurality of master cams thereon, a rotatable work support on said bar which is arranged to support a camshaft inaxial alignment with said master camshaft, meanssynchronously to rotate said camshaft and master camshaft, a rotatable master cam follower roller associated with said master cams which is arranged to cause a transverse movement between the grinding wheel and camshaft to grind a predetermined contour on a cam blank, means including a rotatable cam and a follower to move the master cam roller transversely during the grinding operation, and meansincluding a fluid pressure piston and cylinder operatively connected to rotate said cam to.

produce a relative infeeding movement'between the camshaft support and grinding wheel to grind a cam blank to a predetermined size.

4. In a camshaft grinding machine, a rotatable grinding wheel, a longitudinally movable rock bar, a rotatable master camshaft on said bar having a plurality of master cams thereon, a rotatable work support on said bar which is arranged to support a camshaft in axial align ment with said master camshaft, means synchronously to rotate said camshaft and master camshaft, a rotatable master cam follower roller associated with said master cams which is arranged to cause a transverse movement between the grinding wheel and camshaft to grind a predetermined contour on a cam blank, a transversely movable slide which is arranged rotatably to support the master cam roller, and means to move said-slide transversely during the grinding operation to produce a relative feeding movement between the camshaft support and grinding wi'heel to grind a cam blank to a predetermined s ze.

5. In a camshaft grinding machine, a rotat-' able grinding wheel, a longitudinally movable rock bar, a rotatable master camshaft on said bar having a plurality of master cams thereon, a rotatable work support on said bar which is arranged to support a camshaft in axial alignchronously to rotate said camshaft and master camshaft, a rotatable master cam follower roller associated with said master cams which is arranged to cause a transverse movement between the grinding wheel and camshaft to grind a predetermined contour on a cam blank, a transversely movable slide arranged rotatably to support the master cam roller, a rotatable cam and a fol-' lower to cause a transverse movement of said slide and roller, and means to rotate said cam to produce an infeeding movement of said slide to grind a cam blank to a predetermined size.

6. In a camshaft grinding machine, a rotatable grinding wheel, a longitudinally movable,

rock bar, a rotatable master camshaft on said bar having a plurality of master cams thereon, a rotatable work support on said bar which is arranged to support a camshaft in axial alignment with said master camshaft, means synment with said master camshaft, means synchronoualy to rotate said camshaft and master camshaft, a rotatable master cam follower roller associated with said master cams which is arranged to cause a transverse movement between the grinding wheel and camshaft to grind a predetermined contour on a cam blank, a transversely 'movable slide rotatably to support said master cam roller,means including a rotatable cam and a follower to move said slide transversely, and means including a fluid pressure piston and cylinder operatively connected to rotate said cam to cause a transverse movement of said slide and roller and thereby to produces relative approaching feed between the camshaft control mechanism actuated in timed relationwith the movement of said rock bar to actuate the main control valve.

8. In a cam grinding machine having a rotat able grinding'wheel and a transversely movable wheel slide, a longitudinally movable work table and a rock bar thereon, a master camshaft on said rock bar, a rotatable master cam follower, a transversely movable slide to support said follower, a separate fluid motor for said work table,

. rock bar and master cam roller slide, a main control valve in control of said motors, a pilot valve to actuate said mainrcontrol valve. an electric solenoid to shift said pilot valve, and a cycle control mechanism including an electric switch valve to actuate said main control valve, a solenoid to shift said pilot valve, and a cycle control mechanism including a pawl and ratchet actuated by and in timed relation with the rocking movement of said bar during grinding to control an electric switch so as to energize said solenoid and thereby control the grinding cycle.

10. In a cam grinding machine: having-a pivotally mounted camshaft support and master cams andfollower to control the rocking movement of said support, a longitudinally movable table to support said camshaft support, a trans- .versely movable rotatable grinding wheel and slide, a transversely movable slide supporting said follower, said camshaft support, work table and follower slide each being operated by a separate fluid motor, a main control valve in control of all of said motors, a cycle control device including a pawl and ratchet actuated electric switch, connections between said pivotally mounted camshaft support and pawl to actuate the same in timed relation with the rocking of said camshaft support, and electrically controlled mechanism operated by said switch to rock said bar to an inoperative position after a predetermined grinding operation has been completed.

Y CLARENCE J. GREEN. 

